JP4758133B2 - Giant magnetostrictive speaker - Google Patents

Description

  The present invention relates to a giant magnetostrictive speaker that vibrates outside by displacement of a giant magnetostrictive element.

  A magnetostriction phenomenon is known as a phenomenon in which the shape of a substance changes when a magnetic field is applied. In recent years, giant magnetostrictive materials that undergo a dimensional change of 1000 ppm or more when a magnetic field is applied have been developed.

Moreover, this giant magnetostrictive material has a large generated stress, which is 400 kgf / mm ² or more. Furthermore, this giant magnetostrictive material is capable of high-speed response, and some of the dimensions change in less than 1 microsecond.

  Attempts have been made to use this type of giant magnetostrictive material as a rod-like giant magnetostrictive element, to use a dimensional change as an actuator, and to use an actuator using this magnetostrictive element as a driving source of a speaker.

In addition, as what uses the giant magnetostrictive element which made such a giant magnetostrictive material rod shape for a speaker, what was described in the following patent document 1 exists, for example.
Japanese Patent Laid-Open No. 10-145892 (first page, FIG. 1)

  The giant magnetostrictive speaker described in Patent Document 1 is configured to vibrate a window glass surface, a wall surface, a picture or a photo hung on the wall as a diaphragm, and operate as a speaker. In addition, since a wall surface, a picture, a photograph, etc. are members which are relatively easy to vibrate, it is easy to use as a diaphragm.

  However, if such a giant magnetostrictive speaker is placed on the floor surface and the floor surface is used as a diaphragm, or placed on a relatively strong table and the table surface is used as a diaphragm, When the surface or table surface is solid and has a large area, the displacement of the giant magnetostrictive element is used to vibrate the giant magnetostrictive speaker itself, and there is a problem that sufficient volume cannot be obtained as a speaker. appear. In connection with this, there also arises a problem that the giant magnetostrictive speaker cannot output sound with high sound quality and high fidelity.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a giant magnetostrictive speaker capable of realizing an operation with good acoustic characteristics when used on a horizontal plane. To do.

The present invention for solving the above problems is as described below.
The present invention is a bottomed and covered cylindrical shape that constitutes a magnetic path, and one end is fixed to the lid portion of the yoke, the other end is a free end, and is arranged in the cylindrical direction of the yoke. A giant magnetostrictive element that generates a displacement according to a change in the magnetic field, a coil that is arranged around the giant magnetostrictive element in the yoke and generates a magnetic field according to a signal supplied from the outside, and one end of the giant magnetostrictive element A vibration rod that is in contact with the free end and that has the other end that penetrates the central hole at the bottom of the yoke to transmit the displacement of the giant magnetostrictive element to an external object, and that has a flange in the middle, and the vibration A rubber elastic body disposed between the flange provided on the rod and the bottom of the yoke, and a predetermined mass, and the other end of the vibrating rod is external so that the giant magnetostrictive speaker is self-supporting While placed on the object, And a body portion that applies a load to the giant magnetostrictive element through a joint and effectively transmits the displacement of the giant magnetostrictive element to an external object by the mass. is there.
In the giant magnetostrictive speaker, the rubber elastic body is preferably a silicon rubber elastic body.

  In this giant magnetostrictive speaker, a vibrating contact plate having an area larger than the cross-sectional area of the vibrating rod is provided at the other end of the vibrating rod, and the vibrating rod is connected to the giant magnetostrictive element via the vibrating contact plate. It is desirable to transmit the displacement to an external object.

  Further, in this giant magnetostrictive speaker, the vibrating contact plate is made of different materials and different areas depending on the frequency component and amplitude of vibration to be transmitted, and is configured to be freely attached to the other end of the vibrating rod. Is desirable.

  In the super magnetostrictive speaker, the first bias magnet is disposed between one end of the super magnetostrictive element and the lid of the yoke, and is disposed between the other end of the super magnetostrictive element and the vibrating rod. It is preferable that the first bias magnet and the second bias magnet generate a magnetic field in the same direction in the axial direction of the giant magnetostrictive element.

  In the giant magnetostrictive speaker, the giant magnetostrictive element is divided into a first giant magnetostrictive element near the lid of the yoke and a second giant magnetostrictive element near the bottom of the yoke. It is desirable that a third bias magnet for generating a magnetic field in the same direction as the first bias magnet and the second bias magnet is disposed between the magnetostrictive element and the second giant magnetostrictive element.

  In the giant magnetostrictive speaker, it is desirable that the body portion is configured to have a center of gravity below the center of the yoke. For example, it is more preferable that the body portion has a solid bell shape.

According to the present invention, the following effects can be obtained.
In this giant magnetostrictive speaker invention, a giant magnetostrictive element is disposed with one end fixed to a lid portion of a yoke that has a bottomed and covered cylinder and forms a magnetic path, and the other end is a free end. A coil for generating a magnetic field corresponding to a signal is disposed around the giant magnetostrictive element in the yoke. And it arrange | positions so that the displacement of a giant magnetostrictive element may be transmitted to an external object through the vibration rod which has a collar part in the intermediate part. Further, when the other end of the vibrating rod is placed on an external object so that the giant magnetostrictive speaker is self-supporting, the body portion applies a load to the giant magnetostrictive element via the yoke, and the mass of the body portion causes giant magnetostriction. The displacement of the element is effectively transmitted to the external object.

  Thereby, the external object vibrates due to the displacement of the giant magnetostrictive element according to the signal supplied to the coil. Here, a rubber elastic body is sandwiched between the flange provided on the vibration rod and the bottom of the yoke, and the damping force is not added to the vibration caused by the displacement of the giant magnetostrictive element. To quickly converge.

As a result, when the giant magnetostrictive speaker is placed on a horizontal plane and used, an operation with good acoustic characteristics can be realized.
In the invention of the giant magnetostrictive speaker, the displacement of the giant magnetostrictive element is transmitted to an external object via a vibrating contact plate having an area larger than the cross-sectional area of the vibrating rod.

  As a result, when the giant magnetostrictive speaker is placed on a horizontal plane and used, the displacement of the giant magnetostrictive element can be reliably and faithfully transmitted to an external object, and an operation with good acoustic characteristics can be realized.

  Further, in the invention of this giant magnetostrictive speaker, the vibration contact plate is composed of different materials and different areas depending on the frequency component and amplitude of vibration to be transmitted, and is configured to be freely attached to the other end of the vibration rod. When a giant magnetostrictive speaker is placed on a horizontal plane and used, the displacement of the giant magnetostrictive element can be reliably and faithfully transmitted to an external object according to the application and purpose of use, thereby realizing an operation with good acoustic characteristics. be able to.

  In the invention of the super magnetostrictive speaker, the first bias magnet disposed between one end of the super magnetostrictive element and the lid of the yoke, and the other end of the super magnetostrictive element and the vibrating rod. It is desirable that the first bias magnet and the second bias magnet generate a magnetic field in the same direction in the axial direction of the giant magnetostrictive element. Furthermore, a third bias magnet that generates a magnetic field in the same direction as the first bias magnet and the second bias magnet is disposed between the first giant magnetostrictive element and the second giant magnetostrictive element. Is desirable. By doing so, it becomes possible to uniformly apply a bias magnetic field to the giant magnetostrictive element.

  In the invention of the giant magnetostrictive speaker, it is desirable that the body portion is configured to have a center of gravity below the center of the yoke. This low center of gravity enables the displacement of the giant magnetostrictive element to be reliably and faithfully transmitted to an external object when the giant magnetostrictive speaker is placed on a horizontal plane and has good acoustic characteristics. Can be realized.

The best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described below in detail with reference to the drawings.
<First embodiment>
FIG. 1 is a sectional view showing a sectional configuration of the giant magnetostrictive speaker according to the first embodiment of the present invention.

  In the giant magnetostrictive speaker 100 shown in FIG. 1, reference numeral 110 denotes a giant magnetostrictive element in which a giant magnetostrictive material that generates a magnetostriction phenomenon that changes the shape of a substance when a magnetic field is applied is formed in a rod shape. Here, the giant magnetostrictive element 100 is divided into a first giant magnetostrictive element 111 close to the lid side of the yoke and a second giant magnetostrictive element 112 close to the bottom side of the yoke.

  Reference numeral 120 denotes a bias magnet for applying a bias magnetic field in the axial direction of the giant magnetostrictive element 110. Here, 121 is a first bias magnet arranged between one end of the giant magnetostrictive element 111 and the lid side of the yoke, and 122 is a first bias magnet arranged between one end of the giant magnetostrictive element 112 and the vibrating rod. Reference numeral 123 denotes a second bias magnet, and reference numeral 123 denotes a third bias magnet disposed between the giant magnetostrictive element 111 and the giant magnetostrictive element 112. The first bias magnet 111, the second bias magnet 112, and the third bias magnet 113 are magnetic fields in the same direction as the axial direction of the giant magnetostrictive element with respect to the giant magnetostrictive element 111 and the giant magnetostrictive element 112. Is generated.

  A coil 130 is arranged around the giant magnetostrictive element 110 and generates a magnetic field according to a signal supplied from the outside via the wire 132, and is wound around a coil bobbin 132 arranged around the giant magnetostrictive element 110. It is a solenoid coil.

  Reference numeral 140 denotes a yoke having a bottomed and covered cylinder and constituting a magnetic path, and includes an upper yoke 141 composed of an upper part of the cylinder part and a cover part, and a bottom yoke 142 composed of the lower part and the bottom part of the cylinder part. A center hole is provided in the vicinity of the center of the bottom of the bottom yoke 142, and a vibration rod described later passes therethrough. In addition, the upper yoke 141 and the bottom yoke 142 are provided with screw threads that fit into each other at portions where they are in contact with each other. A rod-shaped giant magnetostrictive element 110 is disposed near the central axis of the cylindrical yoke 140, and a coil 130 is wound around the rod-shaped giant magnetostrictive element 110. The yoke 140, the giant magnetostrictive element 110, and a vibration rod 151 described later form a magnetic closed circuit.

  151 is arranged such that one end is in contact with the free end of the giant magnetostrictive element 110 (111) and the other end that penetrates the central hole at the bottom of the bottom yoke 142 transmits the displacement of the giant magnetostrictive element 110 to an external object. Vibration rod. In addition, this vibration rod 151 is comprised so that it may have the collar part 151a in the intermediate part. In addition, the other end side (external object side) of the vibration rod 151 has a contact 152 as a vibration contact plate having an area larger than the cross-sectional area of the vibration rod 151, and the vibration rod 151 is connected via the contact 152. The displacement of the giant magnetostrictive element 110 is transmitted to an external object.

  Reference numeral 160 denotes a damper made of a rubber elastic body disposed between the flange portion 151 a provided on the vibration rod 151 and the bottom portion of the bottom yoke 142. When the upper yoke 141 and the bottom yoke 142 are screwed, the damper 160 is in a state where a contraction-side force is applied.

  170 is provided as a sliding means for reducing the frictional resistance with the center hole of the bottom yoke 142 when the vibrating rod passing through the center hole at the bottom of the bottom yoke 142 vibrates according to the displacement of the giant magnetostrictive element 110. O ring.

  Reference numeral 180 has an internal space for accommodating the yoke 140 and a bottom hole through which the vibration rod 151 passes. Further, the contact 152 has a predetermined mass, and the contact 152 is placed on an external object so that the giant magnetostrictive speaker 100 is self-supporting. The body part is configured to apply a load to the giant magnetostrictive element 100 through the yoke 140 and to effectively transmit the displacement of the giant magnetostrictive element 110 to an external object by the mass. The body portion 180 is configured by being divided into an upper body 181 and a bottom body 182, and the upper body 181 and the bottom body 182 are integrated with the yoke 140 accommodated in the internal space.

  Here, the relationship between the magnetic field H applied to the giant magnetostrictive element 110 and the shape change (magnetostriction) ΔI / I is as shown in FIG. The characteristic example shown here has the characteristic that the magnetostriction increases as the magnetic field H is increased in both positive and negative directions.

  Therefore, by applying a bias magnetic field and changing the magnetic field according to the signal around the bias magnetic field (FIG. 2B), vibration according to the signal can be obtained (FIG. 2C). ). In this case, it is possible to obtain a faithful vibration corresponding to a change in the magnetic field by using a region with good linearity. Therefore, it is desirable to select a bias magnetic field by the bias magnets 111 to 113 at the center of such a region with good linearity.

FIG. 3 is a characteristic diagram showing how the vibration of the giant magnetostrictive speaker 100 due to the displacement of the giant magnetostrictive element 110 is attenuated by applying various materials to the damper 160.
Here, a pulse-like signal is supplied to the coil 130, and the state of vibration immediately after the signal disappears is shown. Although the absolute value of the vibration varies depending on the mass of the giant magnetostrictive speaker 100, the amplitude of the signal, the shape of the coil 130, etc., the conditions other than the material of the damper 160 are made equal in each of FIGS.

  FIG. 3A shows vibration damping characteristics when a coil spring having a spring constant of 7.6 [N / mm] is used as the damper 160, and the vibration does not converge for more than 3 milliseconds. For this reason, the signal waveform supplied to the coil 130 does not match the vibration waveform, the distortion increases, and it is difficult to obtain a faithful vibration corresponding to the change in the magnetic field.

  FIG. 3B shows vibration damping characteristics when a low-elasticity rubber having a hardness of 32 ° is used as the damper 160. The vibration almost converges in about 1 millisecond. For this reason, the signal waveform supplied to the coil 130 and the vibration waveform are substantially coincident with each other, distortion is small, and faithful vibration corresponding to the change in the magnetic field can be obtained.

  FIG. 3C shows vibration damping characteristics when butyl rubber having a hardness of 65 ° is used as the damper 160, and the vibration is almost converged in about 1.6 milliseconds. For this reason, the signal waveform supplied to the coil 130 and the vibration waveform are substantially coincident with each other, distortion is small, and faithful vibration corresponding to the change in the magnetic field can be obtained.

  FIG. 3D shows vibration damping characteristics when silicon rubber having a hardness of 50 ° is used as the damper 160, and the vibration is almost converged in about 2.6 milliseconds. Further, after 0.6 milliseconds have elapsed, the vibrations are regular with a small amplitude. For this reason, the signal waveform supplied to the coil 130 and the vibration waveform are almost in agreement with each other, and although it has a slight reverberation, the distortion is small and it is possible to obtain a faithful vibration corresponding to the change in the magnetic field. Become.

  According to the above configuration, in a state where the other end (contact 152) of the vibration rod is placed on an external object such as a floor or a table so that the giant magnetostrictive speaker 100 is self-supporting, the body unit 180 moves the yoke 140. In addition, a load is applied to the giant magnetostrictive element 110 through the mass, and the displacement of the giant magnetostrictive element 110 is effectively transmitted to an external object by the mass of the body portion 180.

  Thereby, the external object vibrates due to the displacement of the giant magnetostrictive element 110 according to the signal supplied to the coil 130. Here, a damper 160 made of a rubber elastic body is disposed between the flange portion 151 a provided on the vibration rod 151 and the bottom portion of the yoke 140, and extra vibration is caused by the displacement of the giant magnetostrictive element 110. It quickly converges with damping force without adding vibration.

Moreover, when the inventor conducted a separate experiment and measured the frequency characteristics, the following results were obtained.
When the coil spring is used as the damper 160, a severe peak occurs in the vicinity of 2 kHz, and the low frequency gradually decreases, so that a flat frequency characteristic cannot be obtained, and a desirable characteristic as a magnetostrictive speaker can be obtained. could not.

  On the other hand, when a low elastic rubber having a hardness of 32 °, a butyl rubber having a hardness of 65 °, and a silicon rubber having a hardness of 50 ° are employed as the damper 160, a peak as in the case of the coil spring does not occur, and These characteristics were improved, flat frequency characteristics were obtained, and desirable characteristics as a magnetostrictive speaker were obtained. For this reason, the signal waveform supplied to the coil 130 and the vibration waveform are substantially matched over a wide frequency range, the level difference due to the frequency is small, and it is possible to obtain a faithful vibration corresponding to the magnetic field change. .

  As a result, when the giant magnetostrictive speaker 100 is used while being placed on a horizontal surface such as a floor or a table, an operation with good acoustic characteristics can be realized by using the rubber elastic body as the damper 160.

  In the giant magnetostrictive speaker 100, the displacement of the giant magnetostrictive element 110 is transmitted to an external object via a contact 152 as a vibrating contact plate having an area larger than the cross-sectional area of the vibrating rod 151. As a result, when the giant magnetostrictive speaker 100 is placed on a horizontal plane and used, the displacement of the giant magnetostrictive element 110 can be reliably and faithfully transmitted to an external object, and an operation with good acoustic characteristics can be realized. it can.

  Further, in this giant magnetostrictive speaker 100, the contact 152 as the vibration contact plate has different materials and different areas depending on the frequency component (wide / narrow frequency characteristics) and amplitude (large / small volume) of vibration to be transmitted. It is preferable that it is comprised. And it is preferable that the other end of the vibration rod 151 is configured to be freely mounted by screwing or the like. In this way, when the giant magnetostrictive speaker 100 is placed and used on a horizontal plane, the displacement of the giant magnetostrictive element can be reliably and faithfully transmitted to an external object according to the application and purpose of use. An operation with good acoustic characteristics can be realized. Further, the material and area of the contact 152 as the vibration contact plate may be changed according to the material, hardness, vibration absorption, etc. of the floor or table as the external object.

  In the giant magnetostrictive speaker 100, the giant magnetostrictor 110 is divided into a first giant magnetostrictive element 111 and a second giant magnetostrictive element 112, and sandwiched between three bias magnets, thereby providing a uniform magnetic field to the giant magnetostrictive element 110. Therefore, it is possible to provide an operation with good acoustic characteristics.

  Further, in the giant magnetostrictive speaker 100, the body portion 180 is configured as a low center of gravity as a shape similar to a conical shape or a solid bell shape so as to have a center of gravity below the center of the yoke 140. In order to obtain a low center of gravity, the bottom body 182 may be made of a different material having a specific gravity greater than that of the upper body 181. By setting the body portion 180 to have a low center of gravity in this way, when the giant magnetostrictive speaker 100 is placed and used on a horizontal plane, the body portion 180 can stably stand by itself, and the displacement of the giant magnetostrictive element 110 can be reliably and reliably provided. It becomes possible to transmit to an external object faithfully, and an operation with good acoustic characteristics can be realized.

  In addition, by matching the impedance characteristics of the coil 130 with the characteristics of a general speaker (about 4Ω to 16Ω), it becomes possible to handle connections with various audio devices in the same way as a general speaker. This eliminates the need for special equipment and wiring, and improves usability.

<Second embodiment>
FIG. 4 is a cross-sectional view showing a cross-sectional configuration of a giant magnetostrictive speaker 100 ′ according to the second embodiment of the present invention. The giant magnetostrictive speaker 100 ′ of the second embodiment shown in FIG. 4 basically has a cross-sectional configuration similar to that of the giant magnetostrictive speaker of the first embodiment shown in FIG. For this reason, the duplicate description is abbreviate | omitted by attaching | subjecting the same number to the same thing.

  The giant magnetostrictive speaker 100 ′ of the second embodiment includes a signal amplifier 190. The signal amplifier 190 is supplied with power from the outside via a wire 192a and supplied with a signal from the outside via a wire 192b. Further, the signal amplified by the signal amplifier 190 is supplied to the coil 130 via a signal line not shown here.

  According to the above-described configuration, the body portion 180 is disposed in the yoke 140 in a state where the other end (contact 152) of the vibration rod is placed on an external object such as a floor or a table so that the giant magnetostrictive speaker 100 ′ is self-supporting. In addition, a load is applied to the giant magnetostrictive element 110 via the, and the displacement of the giant magnetostrictive element 110 is effectively transmitted to an external object by the mass of the body portion 180.

  As a result, the external object vibrates due to the displacement of the giant magnetostrictive element 110 according to the signal amplified by the amplifier 190 and supplied to the coil 130. Here, a damper 160 made of a rubber elastic body is disposed between the flange portion 151 a provided on the vibration rod 151 and the bottom portion of the yoke 140, and extra vibration is caused by the displacement of the giant magnetostrictive element 110. It quickly converges with damping force without adding vibration.

As a result, when the giant magnetostrictive speaker 100 ′ is used while being placed on a horizontal surface such as a floor or a table, an operation with good acoustic characteristics can be realized.
As for the configuration or modification of the contact 152, an operation with good acoustic characteristics can be realized as in the first embodiment. With respect to the arrangement of the giant magnetostrictive element 100 ′ and the bias magnet 120, an operation with good acoustic characteristics can be realized as in the first embodiment.

  Further, in the giant magnetostrictive speaker 100 ′, the body portion 180 is configured as a low center of gravity as a shape similar to a conical shape or a solid bell shape so as to have a center of gravity below the center of the yoke 140. In order to obtain a low center of gravity, the bottom body 182 may be made of a different material having a specific gravity greater than that of the upper body 181. By setting the body portion 180 to have a low center of gravity in this way, when the giant magnetostrictive speaker 100 ′ is placed on a horizontal plane and used, the body portion 180 can stably stand on its own and the displacement of the giant magnetostrictive element 110 can be reliably ensured. In addition, it is possible to faithfully transmit to an external object, and an operation with good acoustic characteristics can be realized.

  In such a body portion 180, a space is provided in the lower portion, and the signal amplifier 190 is disposed in the space, so that the body portion 180 can be effectively used. In this case, the signal amplifier 190 is held by the bottom cover 183.

Further, if the body portion 180 is made of metal, it can also serve as a heat radiating means of the signal amplifier 190, and good performance can be obtained.
In addition, by making the input level of the signal amplifier 190 coincide with the input characteristics of a general powered speaker, it becomes possible to handle connections with various portable audio devices in the same way as a general powered speaker. There is no need for consideration, and usability is improved.

<Other embodiments>
In the above description, the body portion 180 has been described as having a conical shape or a solid bell shape so as to have a center of gravity below the center of the yoke 140, but other shapes, for example, pyramid-shaped bottom surfaces having different shapes are used. Various other shapes may be used. Moreover, even if it is cylindrical shape, you may make it implement | achieve a low center of gravity by making an upper part light and making a lower part heavy.

It is a block diagram which shows the structure of the giant magnetostrictive speaker of 1st embodiment of this invention. It is a characteristic view which shows the characteristic of the super magnetostrictive element of the super magnetostrictive speaker of 1st embodiment of this invention. It is a characteristic view which shows the characteristic at the time of changing the material of the damper of the giant magnetostrictive speaker of 1st embodiment of this invention. It is a block diagram which shows the structure of the giant magnetostrictive speaker of 2nd embodiment of this invention.

Explanation of symbols

100 Giant Magnetostrictive Speaker 101 Control Unit 110 Giant Magnetostrictive Element 111 First Giant Magnetostrictive Element 112 Second Giant Magnetostrictive Element 120 Bias Magnet 121 First Bias Magnet 122 Second Bias Magnet 123 Third Bias Magnet 130 Coil 140 Yoke 141 Upper Yoke 142 Bottom Yoke 151 Vibrating rod 152 Contact 160 Damper 170 O-ring 180 Body portion 181 Upper body 182 Bottom body

Claims (6)

A yoke having a bottomed and covered cylinder and constituting a magnetic path;
A giant magnetostrictive element having one end fixed to the lid of the yoke and the other end configured as a free end, arranged in a cylindrical direction of the yoke, and generating a displacement in accordance with a change in a magnetic field;
A coil disposed around the giant magnetostrictive element in the yoke and generating a magnetic field according to a signal supplied from the outside;
One end is in contact with the free end of the giant magnetostrictive element, and the other end penetrating the central hole at the bottom of the yoke is disposed so as to transmit the displacement of the giant magnetostrictive element to an external object, and a flange is provided in the middle part. A vibrating rod having,
A rubber elastic body disposed between the flange provided on the vibrating rod and the bottom of the yoke;
A load is applied to the giant magnetostrictive element through the yoke in a state where the other end of the vibrating rod has a predetermined mass and the other end of the vibrating rod is placed on an external object so that the giant magnetostrictive speaker is independent. A body that effectively transmits the displacement of the giant magnetostrictive element to an external object by mass;
A vibration contact plate configured with different materials and different areas according to the frequency component and amplitude of vibration to be transmitted, configured to be attachable to the other end of the vibration rod, and transmitting the displacement of the giant magnetostrictive element to an external object;
A giant magnetostrictive speaker characterized by comprising: A yoke having a bottomed and covered cylinder and constituting a magnetic path;
A giant magnetostrictive element having one end fixed to the lid of the yoke and the other end configured as a free end, arranged in a cylindrical direction of the yoke, and generating a displacement in accordance with a change in a magnetic field;
A coil disposed around the giant magnetostrictive element in the yoke and generating a magnetic field according to a signal supplied from the outside;
One end is in contact with the free end of the giant magnetostrictive element, and the other end penetrating the central hole at the bottom of the yoke is disposed so as to transmit the displacement of the giant magnetostrictive element to an external object, and a flange is provided in the middle part. A vibrating rod having,
A silicon rubber elastic body disposed between the flange provided on the vibrating rod and the bottom of the yoke;
A load is applied to the giant magnetostrictive element through the yoke in a state where the other end of the vibrating rod has a predetermined mass and the other end of the vibrating rod is placed on an external object so that the giant magnetostrictive speaker is independent. A body that effectively transmits the displacement of the giant magnetostrictive element to an external object by mass;
A giant magnetostrictive speaker characterized by comprising: Different materials depending on the frequency components and amplitude of heat reaching the vibration, is composed of different areas, attached freely configured on the other end of the vibrating rod, further vibration contact plate for transmitting the displacement of the super-magnetostrictive element to an external object Have
The giant magnetostrictive speaker according to claim 2 . A first bias magnet disposed between one end of the giant magnetostrictive element and the lid of the yoke;
A second bias magnet disposed between the other end of the giant magnetostrictive element and the vibrating rod;
And
The first bias magnet and the second bias magnet generate a magnetic field in the same axial direction of the giant magnetostrictive element,
The giant magnetostrictive speaker according to any one of claims 1 to 3. The giant magnetostrictive element is divided into a first giant magnetostrictive element near the lid of the yoke and a second giant magnetostrictive element near the bottom of the yoke;
A third bias magnet that generates a magnetic field in the same direction as the first bias magnet and the second bias magnet is disposed between the first giant magnetostrictive element and the second giant magnetostrictive element.
The giant magnetostrictive speaker according to claim 4. The body portion is configured to have a center of gravity below the center of the yoke.
The giant magnetostrictive speaker according to any one of claims 1 to 5, wherein

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